Biology review

• 1. MCAS Review2012

2. Chemistry of Life 3. Define OrganicCompounds that contain carbonatoms that are covalently bonded toother elements, typicallyhydrogen, oxygen, and other carbonatoms C-H-O 4. All living things are made up of 6essential elements: SPONCHName the 6 elements of life: Sulfur Phosphorus Oxygen Nitrogen Carbon Hydrogen 5. Elements join together bychemical bonds to formcompounds. Name the 3 types ofchemical bonds Covalent Bonds Ionic Bonds Hydrogen Bonds 6. There are 4 major categories oforganic molecules that are madeup of the SPONCH elements. Lipids Carbohydrates Proteins Nucleic Acids 7. LipidsElements: Carbon, Hydrogen, OxygenStructure: 3 fatty acid chains linked by a glycerol backboneFunction: Building blocks of the cellmembrane, energy storingmoleculesExamples: Steroids like cholesterol & fats 8. CarbohydratesElements: Carbon, Hydrogen, OxygenStructure: Monosaccharides bonded together in long chains (poly)Function: Key source of energy!Examples: Sugar and starch 9. ProteinsElements: Carbon, Hydrogen, Oxygen, &NitrogenStructure: Amino acids bonded in longchains that coil around eachother into specific shapesFunction: Enzymes (speed upreactions), structural(hair, muscle, skin, etc), antibodies(protect body)Examples: Enzymes, collagen, antibodies 10. Nucleic AcidsElements: Carbon, Hydrogen, Oxygen, Nitrogen & PhosphorusStructure: Long chain of nucleotides bonded togetherFunction: DNA (store genetic info), andRNA (aid in building proteins)Examples: DNA, RNA 11. Define Chemical Reaction: The process during which chemical bondsbetween atoms are broken and new onesare formed, producing one or moredifferent substances AB + CDAC +BD 12. Write an example of a chemicalreaction and label the reactantsand products: NaCl Na+ + Cl- ReactantProducts 13. Define Activation Energy The energy needed to start a chemicalreaction 14. Define Enzyme: Proteins that increase the speed of achemical reaction 15. Any factors that affect the shapeof an enzyme affect the enzymesactivity. What effect does pH and temperaturehave on an enzymes function? pH and temp must be within an optimalrange for an enzyme to do its job If pH and/or temp are not in the properrange then the enzyme may change shapeor become inactive 16. Cell Biology 17. Draw a Plant Cell 18. Draw an Animal Cell 19. Complete the Table:Cell Part Function (job)Plant/Animal/BothPlasmaEncloses the cell & separates BothMembranethe cytoplasm from itssurroundings, regulates whatenters & leaves the cellNuclear Separates the nucleus fromBothEnvelopethe cytoplasmNucleus Stores DNA and makes mRNA BothNucleolus Located inside the nucleus, BothmRNA is made here 20. Complete the Table:Cell PartFunction (job) Plant/Animal/BothCytoplasmInterior part of the cell made Both up of fluid that cushions all organellesMitochondria Provide energy to the cell BothEndoplasmicProcess & modify proteinsBothreticulumthat were made in the nucleolusGolgiPackage proteins into vesicles Bothapparatusfor export throughout the cell 21. Complete the Table:Cell Part Function (job) Plant/Animal/ BothLysosomeContain digestive enzymes to Bothclean up the cellRibosomeAid in protein synthesis BothVacuole Help digestion of materials, Plantstore nutrients & keep cellpressureCell Wall Support & maintain shape,Plantprotect cell from damage,connect to nearby cells 22. Complete the Table:Cell PartFunction (job)Plant/Animal/ BothChloroplastUse light energy to makePlant food (carbohydrates) through photosynthesisCytoskeleton Help to maintain cell shape & Both aids in movement of materials in the cellCentrioleHelp the formation of the Animal spindle to move chromosomes during mitosis 23. Prokaryote vs. EukaryoteProkaryoteEukaryote True nucleus No nucleus Organelles No organelles Reproduce either Reproduce asexually sexually or asexually Small Larger Example: bacteria Example: plant, animal,protist, fungi cells 24. Draw the structure of the cell membrane:What is it called?Phospholipid bilayerImage source: library.thinkquest.org 25. Diffusion, Osmosis, & Facilitated Diffusion Diffusion Passive transport across a membrane froman area of high concentration to lowconcentration (downstream)**Does not require energy Osmosis Diffusion of Water**Does not require energy Facilitated Diffusion -Passive transport across a membrane froman area of high concentration to lowconcentration that requires carrier proteins**Does not require energy 26. What are the 6 Kingdoms of Life? Eubacteria Archaebacteria Protista Fungi Plants Animals 27. Identify the formulas: Photosynthesis 6H20 + 6CO2 -> C6H12O6 + 6O2 Cellular Respiration C6H12O6 + 6O2 -> 6H20 + 6CO2 + energy 28. Define Photosynthesis The process that captures the sunlightsenergy in the chloroplast of plant cells andconverts it to glucose (sugar), the food forlife 29. Define Cellular Respiration The process that breaks down glucose tomake energy for the cells to use 30. How are Photosynthesis &Cellular Respiration related? They are opposites! One makes sugar (photosynthesis) One breaks sugar (respiration) 31. Humans need oxygen to be ableto perform cellular respirationand gain ATP energy. What would happen to the oxygen levelson Earth if photosynthesis stopped? Oxygen 32. What happens when a phosphategroup is removed from ATP? Energy is released for the cell to use! 33. Compare the energy levels ofATP, ADP, and AMP to the energylevels of a battery ATP (Adenosine Triphosphate) is like afully charged battery with 3 phosphates ADP (Adenosine Diphosphate) is like apartially charged battery with 2phosphates AMP (Adenosine Monophosphate) is like adead battery with only 1 phosphate 34. Draw and label the phases of thecell cycle:What is the functionof the cell cycle? To successfullymake new cells forgrowth of theorganisms orreplacement ofdead or damagedcells 35. Compare and contrast mitosisand meiosis 36. Describe fertilization usinghaploid, gamete, diploid, andzygote 37. Genetics 38. What is DNA? Deoxyribonucleic acid The material that stores the informationthat determines an organismscharacteristics (traits) 39. Draw and Label a Nucleotide 40. How do nucleotides form thestructure of DNA? Nucleotides linktogether to form achain Correspondingnucleotides match-up according to thebase-pairing rulesto form the secondchain 41. Draw a molecule of DNAHydrogen bondsSugar/PhosphatebackboneNucleotideNitrogen bases 42. What is a double helix? 2 strands ofnucleotidesattached byhydrogen bondsin the middle andtwisted together 43. Base-pairing Rules:Adenine Thymine Guanine - Cytosine 44. What is the relationship betweenGene and DNA? Genes are sections of DNA that code forproteins The rest of the DNA codes for nothing! 45. 3 Steps of DNA Replication:1. DNA helicase unwinds the double helix by breaking the hydrogen bonds, forming the replication fork2. DNA polymerase adds complementary nucleotides to the separated DNA strands3. DNA polymerase continues until it reaches the end of the molecule, forming 2 identical DNA molecules 46. Gene expression is the process of turning the genes in the DNA into a phenotype that can be seenDraw and labelthe 2 phases ofgeneexpression, and where theyhappen in thecell 47. End ProductsReplication Transcription TranslationStart DNA DNA RNAEnd DNA RNA Protein 48. Types of DNA Mutations: 49. What will happen if there is amutation in a gamete? Gametes are egg and sperm cells A mutation would result in a geneticdisorder or failure to fertilize (no zygote) 50. Two parents are heterozygous forbrown eyes Bb x Bb BbGenotype Ratio:BBBBb 1BB:2Bb:1bbbBbbbPhenotype Ratio:3 Brown:1 BlueWhat Percent of the Offspring have Blue Eyes?25% 51. Why do men experience male-pattern baldness more thanwomen? The trait is sex-linked Men only have one X chromosome, sowhatever allele they get for hair, whetherit is the dominant normal or the recessiveallele that causes baldness, it will show. Men have XY and women have XX 52. Using Mendels laws ofsegregation and independentassortment, explain why not alltall people have brown hair. The law of segregation says that duringmeiosis the alleles separate independentlyduring Metaphase II of meiosis The law of independent assortment saysthat homologous chromosomes separateindependently during Metaphase I ofmeiosis The two traits are chosen randomly 53. Describe an example for each ofthe following:Codominance Polygenic traits - Both forms of the trait areSeveral genes control one displayed dalmation dogtrait skin color or hair with black spots colorIncomplete dominance Multiple alleles -Neither allele for the traitMore than 2 alleles for oneis dominant white flowertrait Blood typesX red flower = pink!A, B, AB, O 54. Anatomy & Physiology 55. Describe the 4 levels of structuralorganization in the human body Cells Tissues Organs Organ Systems 56. Digestive SystemFunctionPath of Food (allImportantmajor organs)Digestive EnzymesBreaks down and Mouth pharynx Amylase inabsorbs nutrients epiglottis saliva, breaksfrom food;Esophagus down sugarremoves waste;stomach smallmaintains water intestine largePepsin inbalance intestine rectum stomach, breaks anus down protein Lipase in pancreas, breaks down fat 57. Circulatory System FunctionPath of Blood (all major organs) Transports nutrients, Capillary drops off wastes, hormones, and nutrients to cell & picks up gases waste venule vein right atrium right ventricle pulmonary artery capillaries (lungs) pulmonary vein left atrium right atrium aorta artery arteriole - capillary 58. Excretory System Function of KidneysFunction of Liver Regulate the amount of Secretes bile which helps water and salts in the break down fats and bloodabsorb vitamins; regulatessugar levels in blood 59. Respiratory System Function Path of oxygen/carbondioxide (all majororgans) Move air into and out of Mouth/nose pharynx lungs; controls gasepiglottis larynx exchange between blood trachea bronchi and lungsbronchioles alveoli bronchioles bronchi trachea larynx epiglottis pharynx mouth/nose 60. Nervous SystemFunction Basic Unit TheMajor Neuron (How itComponents Works)RegulatesNeuron is made up Peripheral NS behavior;of dendrites that sensory & motormaintainsreceive anneuronshomeostasis; electrical signalregulates otherwhich is then Central NS brainorgan systems; carried to the cell & spinal chordcontrols sensory body which is thenand motorcarried through thefunctionsaxon and is then passed on to the next neurons dendrites 61. Muscular/Skeletal System Function of Muscles 2 functions of bones Help in movement of Provide shape and support bones; contraction of heart to the body and other organsProduce blood cells and platelets in the marrow of the bone 62. 3 types of muscle tissue Skeletal muscles that move bones Smooth involuntarily controlled; themuscles that cause the stomach tocontract Cardiac involuntarily controlled; is themuscle that makes up the heart 63. 2 Types of Connective Tissue Ligament attaches bone to bone Tendon attaches muscle to bone 64. Define homeostasis The process of maintaining internalstability within an organism 65. Explain how body temp ismaintained When it is cold out, the sensory neurons(nervous system) send a signal to the spinalcord then the brain The brain interprets the signal and sends amessage to the motor neurons The motor neurons trigger the muscles inyour body to contract/relax over and over,which causes the bones to move This increases warmth in the body The heart also beats faster sending warmblood more quickly throughout the body toincrease warmth 66. Evolution & Biodiversity 67. What is Evolution by NaturalSelection? Evolution is the change of a species over time This happens due to some kind of change inthe environment of an organism. It mustadapt or die If there is a mutation or trait that isadvantageous, it will be selected for (naturalselection) Organisms with the advantageous trait arepicked as mates and reproduce moresuccessfully, passing on the good genes Over time, the build-up of differences is calledevolution 68. Example: 69. Evidence for EvolutionFossil Comparative AnatomyGenetic &Record HomologousVestigialmolecular StructuresStructures similaritiesBones from The forearm Whale used Gorilla andLucy show aof penguin, to be a 4- human haverelationship human,legged an almostbetween apes lizard, and animal onidenticaland humans bats all have land and thenhemoglobin the samemoved into protein in the bones the sea andblood evolved so that the pelvis and legs have lost their function 70. Speciation Mutation elephant with NO tusks Reproductive Isolation does not get hunted bypoachers and lives freely Natural Selection live longer since they are nothunted and are selected by other elephants Divergence over time if populations stayseparated they may continually adapt and developmore and more genetic differences New Species if the 2 populations become sogenetically different that they no longer breedsuccessfully, they are considered 2 species 71. Define Species: The basic classification of living things 72. What characteristics areorganisms classified (or grouped)by? Form and structure Behavior Molecular similarities 73. 8 Levels of Classification Domain Kingdom Phylum Class Order Family Genus Species 74. Binomial Nomenclature Rules: The first word is the Genus name and iscapitalized The second word is the species and islowercaseHumans = Homo sapiens 75. Define Biodiversity The variety of organisms, their geneticdifferences, and the communities andecosystems in which they occur 76. How does evolution affectbiodiversity? Evolution by natural selection offers ameans by which organisms can becomemore and more different over time to apoint where they become new species. Every living thing experiences evolution atsome speed The large biodiversity of life on Earth canbe attributed to the process of evolution 77. Ecology 78. What is Ecology? The study of interaction of livingorganisms with one another and with theirphysical environment 79. What are the components of anecosystem? Biotic factors (living) plants, animals,bacteria, fungi Abiotic factors (non-living) soil, water,weather, climate 80. Define Community All the living things in one ecosystem 81. Flow of energy Energy begins with the producers who takethe suns energy and turn it into food Primary consumers (herbivores) obtain theirenergy by eating the producers Energy moves to the secondary consumers(omnivores/carnivores) who obtain theirenergy by eating the herbivores Lastly, when all organisms die, decomposersobtain their energy and recycle it back intothe ecosystem 82. What does a food chain show? The path of energy flow in a specificecosystem Grass -> Rabbit -> Fox -> Wolf 83. How do food chains relate to foodwebs? A food web is made up of manyinterconnected food chains 84. Why are energy pyramids usuallyno more than 4 trophic levels? As you go up the trophic levels in anenergy pyramid, energy is lost as heatfrom the organisms that are not eaten(die) Once you reach the top there is very littleenergy available 85. DecomposersDecomposers belonganywhere outside thepyramid. This isbecause of theirniche. Decomposersniche in anecosystem is toobtain energy fromany dead organismand then to recyclethe nutrients backinto the ecosystem 86. Water Cycle Water starts in thenonliving as vapor inthe atmosphere(clouds) then falls asrain, goes into soil, istaken up by the roots ofplants (now part of theliving) and thentranspired back into theatmosphere 87. Carbon Cycle Carbon in form ofcarbon dioxide(CO2)Cellular RespirationPhotosynthesisCarbon in form of food and living things 88. Nitrogen Cycle Nitrogen in the non-usable form ofnitrogen gasDenitrifyingNitrogen-fixing bacteria bacteriaNitrogen in theusable form of nitrates and ammonia 89. Biological CommunitiesCommensalism CompetitionInteraction between 2When 2 organisms use theorganisms where 1 benefits same resources and there isand the other is neither a struggle to obtain thehelped nor harmedresourcesParasitism MutualismInteraction between 2Interaction between 2organisms where 1 benefits organisms where bothand the other is harmedbenefit Predator/PreyInteraction between 2 organisms where the predator needsto hunt and kill the prey for food/energy in order to survive 90. Define Population A group of organisms of the same speciesliving in one area 91. Factors that affect population sizeand biodiversity: Climate change Loss of resources Changes in symbiotic relationships Pollution due to human activity 92. Good Luck on the MCAS Biology Exam! You can do it!